They’re also hot. Like 130 degrees hot. That’s why Zbrozek, president of the Stanford University Solar Car club, has no interest in driving the zero-emissions racer when the team competes in the World Solar Challenge in Australia.

“If you’re moving, it’s about the ambient air temperature because we’ve got vents in the car,” Zbrozek said of a ride in the car they’ve named Apogee. “If you’re stopped, it’s not fun. We’ve recorded temperatures of 130 degrees in the car. That’s in the U.S. I don’t even want to think about what it will be in Australia.”

Broiling temperatures will be the least of the team’s worries when the race begins Oct. 25. They’ll face long days, grueling terrain and stiff competition while racing 1,800 miles across the outback. Like everyone else, they’ll be chasing the four-time defending champs from Delft University. Zbrozek likes their chances.

“I’m expecting to finish somewhere between fourth and eighth place,” he said. “There are 42 teams.”

Above: Home is a World War II-era Quonset hut that once housed an Air Force radar research station. Don’t let the humble appearance fool you — these guys are serious. Zbrozek (pictured) spent a summer interning at Tesla Motors, where he worked with the team that designed the car’s battery pack. Another team member used junkyard parts to build a homemade replica of the Ariel Atom.

The team was founded in 1986 and prides itself on being entirely student run, though it gets some outside help with fundraising. The team has spent about $90,000 on the car since starting work two years ago. That sounds like a lot, but it’s nothing in solar car racing. Massachusetts Institute of Technology spent almost $250,000 building its 90-mph solar car, Eleanor.

“We’re the scrappy underdog of the upper-level teams,” Zbrozek said. “We’ve got a comfortable, but not elaborate, budget.”

The workshop is as cluttered as Apogee is graceful, and it has a vibe somewhere between dorm room and engineering lab. Equations, notes and diagrams are scrawled on the walls and parts are almost haphazardly scattered about. That’s Jordan LeNoach crunching numbers in the office in the background and a section of Apogee’s upper cowling in the foreground. “Kangaroo crossing” signs are a reminder of where the team is headed and one of the risks it will face during seven days on the road between Darwin and Adelaide.

“Over the course of an eight-hour day, we should be able to do about 400 miles,” Zbrozek said.

Drivers do four-hour stints, and each carries one gallon of water. That’s a lot of water, even if you’re sweating like an ice-cold beer, and there are no pit stops.

“They’re either going to hold it or wet themselves,” Zbrozek said. “We’ve offered our drivers NASA diapers, but no one’s taken us up on it.”

Apogee’s carbon-fiber body was fabricated by hand, using large molds like the one shown above. The car is headed for the wind tunnel at Ames Research Center for final tweaks, and the team is shooting for a superslick drag coefficient of just 0.12. The car looks a bit like a pool table and is about the size of a Tesla Roadster.

Stanford always built four-wheel cars, but a change in the rules requires drivers to sit up instead of stretch out. That prompted the team to switch to the more traditional three-wheel design.

“The more upright driving position puts the driver’s butt down low, so we switched to a three-wheel design because that puts the wheel behind the driver,” Zbrozek said. That, in turns, improves aerodynamic efficiency.

So why the change in the rules?

“They’re trying to push solar cars to be more convergent with road cars,” Zbrozek said.

That’s not as absurd as sounds. Solar racing is a proving ground for batteries, motors and power management systems that could appear in hybrids and EVs. The Chevrolet Volt range-extended electric car is a direct descendant of the Sunraycer that won the inaugural solar challenge in 1987.

“Solar racing has direct applicability to the outside world,” Zbrozek said. “But more than that, building solar cars makes you a really, really good engineer.”

Apogee may be high-tech, but the oven it was baked in was about as low-rent as they come.

“We built it in four hours on a Saturday afternoon using two-by-fours, fiberglass insulation and plastic sheeting,” Zbrozek said. “It’s heated with propane torches. It doesn’t sound very safe, but we got the fire marshal, the engineering department and the department of risk management to sign off on it.”

Carbon fiber must be cured, so the team rolled Apogee into the oven, aimed the torches into the oven “and let ‘em rip for eight hours” at 250 degrees, Zbrozek said. The ironic thing is that rickety-looking oven replaced one that was electrically heated and made of concrete fiber panels.

“It was a perfectly safe outdoor oven,” Zbrozek said. “It was a beautiful, beautiful piece of work and the university deemed it unsafe.”

Zbrozek does what he can to keep things organized, which is important because just about everything in Apogee was hand-made. Even the inductors in the car’s power supply were wound by hand. About the only off-the-shelf parts are the motor, the battery cells and the motor controller.

“It’s one of the most complicated things on the car,” Zbrozek said of the controller. “Thank God we just buy it.”

Apogee rides on a carbon fiber monocoque chassis with Nomex honeycomb structural members. A steel roll cage and five-point safety harness protect the driver. Good thing, too, because Equinox, the team’s 2007 entry, flipped over in a crash about two-thirds of the way through the race across Australia.

“The left rear tire had a very slow leak,” Zbrozek said. “The driver noticed the car pulling to the side and oscillating. Just as he started to pull over, the rear end started oscillating badly. He lost grip and started to slide at 55 or 60 mph. Normally a solar car won’t flip because the center of gravity is so low, but he hit a concrete embankment and flipped.”

The driver wasn’t hurt, but the crash made a mess of the rear suspension. Repairs took several days, but the team got Equinox back on the road and across the finish line. They lost so much time, though, that race officials classified the car as “did not finish.”

The front suspension components are milled from billet aluminum and ride on Fox shock absorbers. Those beefy brakes are designed for junior dragsters and can bring the car to a stop in a hurry.

“We don’t want to not have the brakes if we need them,” Zbrozek said. “Most teams use bicycle brakes. They suck.”

The tires are Dunlops designed specifically for solar car racing. They’re superthin — the rubber is just 1/16-inch thick — and inflated to 125 psi to minimize rolling resistance.

“They’re like bicycle tires but they don’t have innertubes,” Zbrozek said.

Propulsion comes from a hub-mounted 3-phase AC motor. It drives the wheel at 2 kilowatts (2.68 horsepower) continuous and 10 kilowatts (13.41 horsepower) peak power. That may no sound like much, but Apogee has a cruising speed of 45 to 55 mph and a theoretical top speed of 83 to 90 mph.

“We hit 65 out at Laguna Seca, but we didn’t have a long enough straight to get it fully up to speed,” Zbrozek said.

The motor is set up for maximum acceleration, not top speed, and Zbrozek claims it has a cruising efficiency of 96 percent. The motor costs $12,000, which explains why the team pulled it out of Equinox and used it again in Apogee.

Minimizing weight while maximizing strength is key in any race car, but especially in one powered only by the sun. Even the steering wheel is made of carbon fiber, which helps keep the car’s weight down to 550 pounds — with the driver. The rules stipulate 180 pounds for the driver, so if the person behind the wheel weighs less than that, the team adds ballast to make up for it.

Apogee will draw power from 402 photovoltaic cells, each just 120 microns thick. They’ll cover six square meters of the car.

“They’ll generate a hair under 1.4 kilowatts,” Zbrozek said.

That’s enough to run a hair dryer or a pair of laptop computers. Power is stored in a 4.8 kilowatt-hour battery, which also gets a boost from regenerative braking. The regen system can return as much as 200 kilowatts to the battery in eight seconds.

Schematics of the clocks in the processors and a block diagram of the car are just some of the many notes and equations scrawled on whiteboards throughout the workshop. The diagram in the upper right corner that looks like a hill is a graph showing the power collection of the Sun Power photovoltaic cells.

The team has to build more than a car — it has to outfit the support and chase vehicles as well. Erica Brett is building a rack to hold all the communication equipment in the van that will follow Apogee across Australia.

The accelerator and brake pedals were milled from billet aluminum and are almost too gorgeous to hide in the car.

Racing across Australia requires more than getting in, buckling up and stomping the accelerator. A successful race depends upon a strategy that considers everything from road conditions and terrain to the weather forecast. The team also monitors battery voltage, temperature and other data using a telemetry system in the car.

“We can tell exactly how much energy the car is using and how much energy it’s going to need and how fast to go to maximize our efficiency,” Zbrozek said.

Analyzing all that data lets the team know, for example, if it should creep over a hill or speed up one side and recover the energy with regenerative braking going down the other side.

“Winning the race comes down to using your energy efficiently,” he said.

The pack cost about $5,000 and weighs 25 kilograms. Everyone competing in the Solar Challenge starts with a full charge, and Apogee’s battery is good to go in two hours at 240 volts. Range is about 200 miles.

“If you convert that to mpg, it comes out to about 1,300 mpg-equivalent — which, incidentally, is about 10 times better than the Tesla,” Zbrozek said.

The team took first place in the stock class at the 2005 World Solar Challenge with Solstice. The car sits in a trailer outside the workshop and makes occasional appearances at campus events and the like. So why drag out a four-year-old car instead of something newer?

“If some 6-year-old kid sits on it, we don’t have to worry about the car breaking,” Zbrozek said. “That actually happened once. We had a kid butt-slam the car once. He just whacked it. People actually heard it break. It sounded like a gunshot. That’s why we don’t bring a new car to public events.”

It’s definitely cramped inside the car, although the pedals can be adjusted fore and aft to provide a bit of legroom. There’s no air conditioning, but ducts in the bodywork provide some air flow. A small camera mounted at the back of the car provides a view of what’s behind you.

A change in the rules has the drivers sitting upright this year instead of stretching out almost flat.

“Your butt is, like, five inches off the ground,” Zbrozek said. “Our new car will be much more comfortable than the last one.”

Maximizing aerodynamic efficiency is the name of the game with electric cars, especially those powered by the sun. The smallest possible bubble for the driver’s head and slick fairings over the wheels improve airflow.